A conventional cutter head assembly for a wood planing machine includes a drive shaft, a blade carrier and a plurality of cutting blades. The drive shaft has a longitudinal axis. The blade carrier surrounds the drive shaft, extends parallel to the longitudinal axis, and is retained on the drive shaft. The cutting blades are spacedly disposed on the blade carrier and surround the longitudinal axis. Each of the drive shaft and the blade carrier is made of iron, so that the weight of the conventional cutter head assembly is heavy. Further, after using the conventional cutter head assembly for a long period of time, the blade carrier may rust, and the cutting blades disposed on the blade carrier may loosen. Moreover, the cost of the iron blade carrier is expensive.